- Telephone:+31 20 59 87217
- Room nr:h-119
- Unit:faculteit der aard- en levenswetenschappen ( subafdeling dierecologie )
During my PhD I will focus on the interaction between Folsomia candida and Wolbachia pipientis. It is known that Wolbachia can induce parthenogenesis in several invertebrate species. Of F. candida we have both a parthenogenic line that is infected with Wolbachia and a sexual line that is not. By infecting the sexual line and monitoring the genetic and physiological changes we will try to find out if and how Wolbachia manipulates F. candida towards parthenogenisis.
I’m interested in complications that can arise when organisms interact, since in my opinion this is a field of science that should be better explored. A better understanding of these interactions can for example lead to better ways of pests control, better understanding of ecosystem functioning and co-evolutionary drivers. Throughout my master I looked at the effects of pesticides on a tritrophic system that included a wheat plant, aphids and a parasitic wasp and at the influence of combinations of different organisms classified by functional traits on decomposition. During this second internship we also developed a tool to assess the decomposition rate in aquatic environments called the DECOTAB.
Quantify the rate and succession of evolutionary changes induced by ecological interactions
The key objective of this project is to identify the initial molecular and phenotypic changes induced by ecological interactions using experimental evolution, and to track the progression of changes across different stages of symbiotic dependency, which will provide insight into the potential evolutionary trajectories towards compensated trait loss.
This will be accomplished by infecting a strain of sexual reproducing F. candida and a strain of closely related sister species F. fimetaria. After infection molecular and phenotypic changes will be monitored and compared to long term infected, parthenogenic F. candida and uninfected F. fimentaria.
This project is part of a larger Vici project about the evolutionary loss of traits in ecological interactions. This Vici project aims to develop a new framework for understanding the driving forces and underlying mechanisms of trait loss and its evolutionary consequences in the context of ecological interactions. At present, the prevalence of trait loss is likely to be grossly underestimated because trait loss is not always accompanied by loss of function, due to provision of resources by ecological interactions. If resources are supplied by a symbiotic partner or by dietary intake, the underlying trait becomes redundant and is prone to loss or degradation. However, the evolutionary dynamics driving such compensated trait loss are poorly understood, despite its potential importance for long-term stability of ecological interactions. By using a coherent set of model systems in which cases of compensated trait loss were uncovered previously, we will study the evolution of compensated trait loss through a combination of three complementary approaches:
1. Comparative genomic approach to identify molecular mechanisms underlying trait loss, and investigate similarities of genes involved in parallel events of trait loss;
2. Experimental evolution to track evolutionary changes induced by ecological interactions, and link this to changes in gene expression;
3. Phylogenetic approach to elucidate the evolutionary history of compensated trait loss, and determine the potential for replicated evolution and reversal of trait loss.
By combining these three approaches we expect to significantly impact the understanding of mechanisms that drive evolution.
Participants: Jacintha Ellers, Ken Kraaijeveld and Janine Mariën
Partners: Francesco Frati and Paolo Fianculli (University of Siena)
Hunting, E.R. and A.A. Kampfraath(2013) Contribution of bacteria to redox potential (Eh) measurements in sediments. International Journal of Environmental Science and Technology, 10: 55-62.
Kampfraath A.A., E.R. Hunting, C. Mulder, A.M. Breure, M.O. Gessner, M.H.S. Kraak and W. Admiraal (2012). DECOTAB – a multipurpose standard substrate to assess effects of litter quality on microbial decomposition and invertebrate consumption. Freshwater Science, 31(4): 1156-1162.